The only benefit that I can see would be decreased energy consumption. The 4ft. T5HO bulbs are 54W, so you would be getting about the same amount of PAR for abotu 40% less electricity, plus you have more bulb options with T5 as far as K ratings go. Hope this helps, I'm not too sure how hard changing the wiring around would be, but I'm sure you can find a wiring diagram on the Icecap website.